Speaker Prof. Zhen-yu YIN Associate Professor Research Institute of Civil Engineering and Mechanics Ecole Centrale de Nantes, France Abstract The elementary mechanical behaviors and constitutive modeling of soft soils is an important theoretical basis for the engineering practice on soft soil regions. This presentation focuses on some typical mechanical behaviors of soft soils starting from the most basic materials “remolded soils to intact natural. Each basic characteristics is presented from its definition or basic description, then to introduce the testing methods with summary and analysis of test results, as well as commonly used constitutive modeling methods. Biography Dr Yin graduated from Zhejiang University in 1997 for BSc, and then worked as engineer at Zhejiang Jiahua Architecture Design Institute for five ...

Speaker Prof. Gang WANG Associate Professor Department of Civil and Environmental Engineering School of Engineering Hong Kong University of Science and Technology Hong Kong Abstract Understanding the fundamental mechanism of soil liquefaction is one of the major challenges in geotechnical earthquake engineering and soil dynamics. In this talk, I present numerical modeling of soil liquefaction from both macroscopic and micromechanical perspectives. First, a bounding-surface hypoplasticity model is developed to capture the macroscopic behaviors of sands during various phases of undrained cyclic loading. The model utilized a new modulus formulation to improve the simulation of cyclic mobility and post liquefaction behaviors of both loose and dense sands. Second, micromechanical perspectives of the liquefaction process are investigated using the Discrete Element simulation. ...

Speaker Prof. Shi-Jin FENG Professor Department of Geotechnical Engineering College of Civil Engineering Tongji University, Shanghai, China Abstract Landfill gas (LFG) emission and explosion, leachate leakage and diffusion, deformation and stability are the main concerns in municipal solid waste (MSW) landfills recently. These problems are closely related to the migration and blocking of leachate and LFG. In this study, two-dimensional LFG flow analytical models are developed for layered landfills with horizontal or combined LFG collection systems. An optimized design method is also proposed accordingly. Moreover, an axisymmetric numerical model incorporating MSW compression and leachate recirculation is established to describe the transient LFG flow in bioreactor landfills. The saturated-unsaturated leachate migration under different recirculation systems is also investigated using 3D numerical ...